Physical Properties of Coal
Physical properties of rocks are used to identify the type of rocks and to discover more about them. There are various physical properties of Coal like Hardness, Grain Size, Fracture, Streak, Porosity, Luster, Strength etc which defines it. The physical properties of Coal rock are vital in determining its Coal Texture and Coal Uses.
Hardness and Strength of Coal
The physical properties of Coal depend on its formation. Physical properties of rocks play an important role in determining its applications in various fields. Rocks are rated on the on the Moh's Hardness Scale which rates the rocks on the scale from 1 to 10. Rocks with hardness 1-3 are soft rocks from 3-6 are medium hardness rocks and 6-10 are hard rocks. The hardness of Coal is 1-1.5 whereas its compressive strength is Not Available. Streak is the color of rock when it is crushed or powdered. The streak of Coal is black whereas its fracture is conchoidal. Luster of Coal is the interaction of light with the surface of Coal. Luster of Coal is dull to vitreous to submetallic. Coal cleavage is non-existent. The specific gravity of Coal is 1.1-1.4. Coal is opaque in nature whereas its toughness is not available. You can also know all the list of rocks in Opaque Rocks, Translucent Rocks and Transparent Rocks.